Two letters in an Infiniti model name let you know that the vehicle packs some extra punch. The 2007 Infiniti QX56 luxury SUV doesn't disappoint after getting a 5-horsepower increase to 320 hp in its 5.6-liter V8 engine. This four-door model seats 8 in 3 rows and comes in two trims: 2WD and AWD. SUVs have a notorious reputation for gas-guzzling, and the QX56 falls right in line with the stereotype. Expect 13 mpg in the city, 18 on the highway. Fold down the second and third rows and you'll get 97 cubic feet of loading space. Inside, you'll get some interesting standard high-tech features, including Bluetooth, a 10-speaker Bose stereo system, leather seats, and wood trim. You'll need to spring a little extra for the rear-seat DVD player and satellite radio. Finally, despite its hefty size, the QX56 remains surprisingly agile, going from 0-60 mph in 7.3 seconds. Overall, drivers enjoy the QX56's power and surprisingly smooth handling for a full-size SUV. Others would prefer a flashier exterior, more cargo space, and better gas mileage. Despite having the drawbacks of your traditional SUV, the 2007 QX56 successfully brings Infiniti up to speed in an increasingly competitive market for high-powered luxury rides.